The overall goals of the Mayo Clinic Urology O'Brien Research Center are to develop new diagnostic strategies in order to accurately phenotype patients and thus apply improved individualized management strategies. We will pursue these goals via 4 interlinked multidisciplinary projects. Important and timely aims of the Mayo Clinic O'Brien Urology Research Center include: 1) Develop and validate a comprehensive low-dose stone-characterization exam using clinical dual-energy CT techniques in order to predict stone fragility, and to develop new CT methods capable of detecting the earliest possible precursor lesions. 2) Determine factors that produce NL precursor lesions including Randall's plaques and tubular plugs. 3) Define specific factors that increase the risk of kidney stones and their recurrence, and develop clinical prediction tools to help clinicians identify high-risk patients. 4) Define environmental and genetic factors that influence oxalate transport and crystallization in a novel high throughput Drosophila model The Administrative Core will oversee Center operations and serve as the interface between the Center and the N.I.H as well as the Mayo Clinic administrative structure. Specific responsibilities of the Core include: 1) Coordinating monthly Executive Committee meetings 2) Monitoring financial performance and progress of each project and core 3) Coordinating the education enrichment program 4) Coordinating the Mayo-funded Pilot program and grooming Pilots for submission to the Opportunity Pool 5) Coordinating the Annual Retreat and O'Brien Center review. These functions will be conducted by a Director, 3 Associate Directors, and a Research Operations Coordinator.